The functions of the Core are to perform biochemical assays on biological samples submitted to the laboratory by the projects that comprise the Program Project in a manner that assures strict quality control both within and between assays, and to report the results to the project staff in a timely manner. During years 1 through 5 of the current project, the Core performed on average 6,200 individual results per year for 23 different analytes in support of all projects. In the current proposal a similar number of results are anticipated (approximately 6,300 tests per year) providing data on 29 individual analytes. New assays developed during the prior project period include homocysteine and hemoglobin A1c for Project 1 and rabbit CRP, oxytocin, and angiotensin for Project 3. An additional function of the Core is to identify and validate new assays in support of individual projects as may be requested. In consultation with the Administrative Core and Project leaders, priority will be evaluated by: number of projects that will utilize the assay;test complexity and availability of appropriate instrumentation; and availability of resources (i.e., funding and staff). The core leaders may also decide to identify other laboratories that may already have such testing in place, especially if such an arrangement provides an economy of resources.